DDR4标准协议
【文件名】:121015@52RD_JESD79-4.pdf
【格 式】:pdf
【大 小】:3965K
【简 介】:
【目 录】:
Contents
1. Scope ......................................................................................................................................................................... 1
2. DDR4 SDRAM Package Pinout and Addressing ........................... .............. ........................................... ................... 2
2.1 DDR4 SDRAM Row for X4,X8 and X16 .......................... .............. .............. .............. ............................................2
2.2 DDR4 SDRAM Ball Pitch ... .............. .............. .............. .............. ........................................... ..................................2
2.3 DDR4 SDRAM Columns for X4,X8 a nd X16 ............ .............. .............. .............. ....................................................2
2.4 DDR4 SDRAM X4/8 Ballout using MO-207 ......................... .............. .............. .................................. .................. 2
2.5 DDR4 SDRAM X16 Ballout using MO-207 ............ .............. .............. .............. .................................. .....................3
2.6 Pinout Description ..................................................................................................................................................5
2.7 DDR4 SDRAM Addressing ................ .............. .............. .............. ............ ................................ ...............................7
3. Functional Description ...............................................................................................................................................8
3.1 Simplified State Diagram ....................................................................................................................................8
3.2 Basic Functionality........................................................................................................ ..........................................9
3.3 RESET and Initialization Procedure ............................ .............. .............. .............................................................10
3.3.1 Power-up Initialization Sequence ............................ .............. .............. ................................ .....................10
3.3.2 Reset Initialization with Stable Power .................................................................................. ....................11
3.4 Register Definition ................................... .............................................................................................................12
3.4.1 Programming the mode registers .................... ...................................................................... ...................12
3.5 Mode Register .............................................................................................................. ........................................13
4. DDR4 SDRAM Command Description and Operation ....... .............. .............. ............ .............................................. 24
4.1 Command Truth Table ........................................................................................................ ..................................24
4.2 CKE Truth Table ...................................................................................................................................................25
4.3 Burst Length, Type and Order ..............................................................................................................................26
4.3.1 BL8 Burst order with CRC Enabled ........................................................................................ .................26
4.4 DLL-off Mode & DLL on/off Switching procedure .................. .............. ............................................. ...................27
4.4.1 DLL on/off switching procedure .......................................................................................... .....................27
4.4.2 DLL “on” to DLL “off” Procedure ......................................................................................... .....................27
4.4.3 DLL “off” to DLL “on” Procedure ......................................................................................... .....................28
4.5 DLL-off Mode ............................................................................................................... .........................................29
4.6 Input Clock Frequency Change ............................................................................................... .............................30
4.7 Write Leveling .......................................................................................................................................................31
4.7.1 DRAM setting for write leveling & DRAM termination fu nction in that mode ............................................32
4.7.2 Procedure Description ............. .............. .............. .............. ....................... ..................... ..........................33
4.7.3 Write Leveling Mode Exit ................................................................................................ .........................34
4.8 Temperature controlled Refresh modes ...............................................................................................................34
4.8.1 Normal temperature mode .......................................................................................................................34
4.8.2 Extended temperature mode ................................................................................................................... 34
4.9 Fine Granularity Refresh Mode .............................................................................................. ..............................35
4.9.1 Mode Register and Command Truth Table ..............................................................................................35
4.9.2 tREFI and tRFC parameters ............................................................................................... .....................35
4.9.3 Changing Refresh Rate ................................................................................................... ........................36
4.9.4 Usage with Temperature Controlled Refresh mode........................................................................... ...... 36
4.9.5 Self Refresh entry and exit .......................................................................................................................37
4.10 Multi Purpose Register .......................................................................................................................................37
4.10.1 DQ Training with MPR ................................................................................................... ........................37
4.10.2 MR3 definition ........................................................................................................................................37
4.10.3 MPR Reads............ .............. .............. .............. .............. ............ ............................... ............................. 38
4.10.4 MPR Writes............................................................................................................................................ 40
4.10.5 MPR Read Data format ........................ .............. .............. .............. ....................... .......... .......................43
4.11 Data Mask(DM), Data Bus Inversion (DBI) and TDQS .......................................................................... .............48
4.12 ZQ Calibration Commands ................................................................................................... ..............................50
[此贴子已经被作者于2012-10-15 17:27:39编辑过] |